Question

Solve the equation by factoring.

Answer 1

Factorizing an expression involves writing the expression in simpler forms

The values of z are $z = \frac 15$ or $z=4$

The equation is given as:

$5z^2 - 21z + 4 = 0$

Expand the equation

$5z^2 - 20z -z + 4 = 0$

Factorize the expression:

$5z(z - 4) -1(z - 4) = 0$

Factor out z - 4

$(5z - 1)(z - 4) = 0$

Split

$5z -1 = 0$ or $z - 4 = 0$

Solve for z

$z = \frac 15$ or $z=4$

Hence, the values of z are $z = \frac 15$ or $z=4$

Read more about factorization at:

brainly.com/question/11579257

Answer 2

I would say the answer would be D by my calculations if I'm wrong I will come back and update